1. Technical Field
This document relates to methods and materials involved in modulating (e.g., increasing or decreasing) oil levels in plants. For example, this document provides plants having increased oil levels as well as materials and methods for making plants and plant products having increased oil levels.
2. Incorporation-by-Reference & Texts
The material on the accompanying diskette is hereby incorporated by reference into this application. The accompanying compact discs contain one identical file, 11696-204WO1-Sequence.txt, which was created on Jan. 26, 2007. The file named 11696-204WO1-Sequence.txt is 1128 KB. The file can be accessed using Microsoft Word on a computer that uses Windows OS.
3. Background Information
Fat, protein, and carbohydrates are nutrients that supply calories to the body. Fat provides nine calories per gram, which is more than twice the number provided by carbohydrates or protein. Dietary fats are composed of fatty acids and glycerol. The glycerol can be converted to glucose by the liver and used as a source of energy. The fatty acids are a good source of energy for many tissues, especially heart and skeletal muscle.
Fatty acids consist of carbon chains of various lengths and a terminal carboxylic acid group. Saturated fatty acids do not contain any double bonds or other functional groups along the chain. A saturated fatty acid has the maximum possible number of hydrogen atoms attached to every carbon atom. Therefore, it is said to be saturated with hydrogen atoms. Eating too much saturated fat is one of the major risk factors for heart disease. Saturated fats are found in animal products such as butter, cheese, whole milk, ice cream, cream, and fatty meats. Saturated fats are also found in some vegetable oils, such as coconut, palm, and palm kernel oils. Most other vegetable oils contain unsaturated fat that helps to lower blood cholesterol if used in place of saturated fat.
Unsaturated fatty acids contain one or more double bonds between carbon atoms and, therefore, two fewer hydrogen atoms per double bond. A fatty acid with a single double bond is called a monounsaturated fatty acid. A fatty acid with two or more double bonds is called a polyunsaturated fatty acid. Polyunsaturated fats are liquid at room temperature, and remain in liquid form even when refrigerated or frozen. Polyunsaturated fats are divided into two families: the omega-3 fats and the omega-6 fats.
The omega-3 family of fatty acids includes alpha-linolenic acid (ALA). ALA is an essential fatty acid that cannot be synthesized in the body and must, therefore, be consumed in the diet. Dietary sources of ALA include canola, flaxseed, flaxseed oil, soybean, and pumpkin seed oil. Omega-3 fatty acids have been found to reduce the risks of heart problems, lower high blood pressure, and ameliorate autoimmune diseases.
Omega-6 fatty acids are beneficial as well. The omega-6 family of fatty acids includes linoleic acid, which is another essential fatty acid. The body converts linoleic acid to gamma linoleic acid (GLA) and ultimately to prostaglandins, which are hormone-like molecules that help regulate inflammation and blood pressure as well as heart, gastrointestinal, and kidney functions. The main sources of omega-6 fatty acids are vegetable oils such as corn oil and soy oil.
Vegetable oil is fat extracted from plant sources. Vegetable oils are used in cooking, in making margarine and other processed foods, and in producing several non-food items such as soap, cosmetics, medicine, and paint. Since vegetable oils are usually extracted from the seeds of the plant, seed oil yield has a significant impact on the economics of producing many products. Increasing seed oil content may increase the economic return per unit to the seller of the seed in addition to increasing the nutritional value to the consumer of the seed.